R programming: packages

Published

January 16, 2026

M1 MIDS/MFA/LOGOS

Université Paris Cité
Année 2025

Course Homepage

Moodle

This lab is just an incentive to dig into R Packages (2e) by Wickham and Bryan

Introduction

Sharing/Storing/Organizing

Packages come with conventions

Packaging can be helpful to perform data analysis.

Setup

Automating package development is facilitated by a collection of packages.

Code

devtools is the cornerstone of the collections

  • with rstudio (hands in hands)
  • with vs code
  • with positron

Package organization

Make sure you understand the different states of a package : source, bundled, binary, installed, in-memory.

  • At first, we deal with a source package. Where is it hosted?
  • How is the source organized?
  • What are metadata for?
  • What is the purpose of file .Rbuildignore?
  • Why do we bundle packages?

Structure and states of a package

To initialize a package development directory.

Code
packpath <- "hmw2.ma7by020"

if (!fs::dir_exists(packpath)){

  fs::dir_create(packpath)
}

usethis::create_package(packpath)

Within directory hmw2.ma7by020, you should have the next organization

hmw2.ma7by020/
├── DESCRIPTION
├── .gitignore
├── hmw2.ma7by020.Rproj
├── NAMESPACE
├── R
└── .Rbuildignore

2 directories, 5 files

What is the difference between loading and attaching a package?

You will have to

  • populate the R subdirectory
  • update DESCRIPTION

Reusing scripts

Styling

Testing

The workhorse of the development process is ::: {.cell}

Code
devtools::load_all()

:::

  1. Code and/or fix bugs
  2. Load the code
  3. Test the code

Checking Package state

Code
devtools::check()

NAMESPACE and dependencies

Versioning (git)

References

Writing R extensions